PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Gold nanoparticles give an edge in recycling CO2

2013-10-25
(Press-News.org) Contact information: Kevin Stacey
kevin_stacey@brown.edu
401-863-3766
Brown University
Gold nanoparticles give an edge in recycling CO2

PROVIDENCE, R.I. [Brown University] — By tuning gold nanoparticles to just the right size, researchers from Brown University have developed a catalyst that selectively converts carbon dioxide (CO2) to carbon monoxide (CO), an active carbon molecule that can be used to make alternative fuels and commodity chemicals.

"Our study shows potential of carefully designed gold nanoparticles to recycle CO2 into useful forms of carbon," said Shouheng Sun, professor of chemistry and one of the study's senior authors. "The work we've done here is preliminary, but we think there's great potential for this technology to be scaled up for commercial applications."

The findings are published in the Journal of the American Chemical Society.

The idea of recycling CO2 — a greenhouse gas the planet current has in excess — is enticing, but there are obstacles. CO2 is an extremely stable molecule that must be reduced to an active form like CO to make it useful. CO is used to make synthetic natural gas, methanol, and other alternative fuels.

Converting CO2 to CO isn't easy. Prior research has shown that catalysts made of gold foil are active for this conversion, but they don't do the job efficiently. The gold tends to react both with the CO2 and with the water in which the CO2 is dissolved, creating hydrogen byproduct rather than the desired CO.

The Brown experimental group, led by Sun and Wenlei Zhu, a graduate student in Sun's group, wanted to see if shrinking the gold down to nanoparticles might make it more selective for CO2. They found that the nanoparticles were indeed more selective, but that the exact size of those particles was important. Eight nanometer particles had the best selectivity, achieving a 90-percent rate of conversion from CO2 to CO. Other sizes the team tested — four, six, and 10 nanometers — didn't perform nearly as well.

"At first, that result was confusing," said Andrew Peterson, professor of engineering and also a senior author on the paper. "As we made the particles smaller we got more activity, but when we went smaller than eight nanometers, we got less activity."

To understand what was happening, Peterson and postdoctoral researcher Ronald Michalsky used a modeling method called density functional theory. They were able to show that the shapes of the particles at different sizes influenced their catalytic properties.

"When you take a sphere and you reduce it to smaller and smaller sizes, you tend to get many more irregular features — flat surfaces, edges and corners," Peterson said. "What we were able to figure out is that the most active sites for converting CO2 to CO are the edge sites, while the corner sites predominantly give the by-product, which is hydrogen. So as you shrink these particles down, you'll hit a point where you start to optimize the activity because you have a high number of these edge sites but still a low number of these corner sites. But if you go too small, the edges start to shrink and you're left with just corners."

Now that they understand exactly what part of the catalyst is active, the researchers are working to further optimize the particles. "There's still a lot of room for improvement," Peterson said. "We're working on new particles that maximize these active sites."

The researchers believe these findings could be an important new avenue for recycling CO2 on a commercial scale.

"Because we're using nanoparticles, we're using a lot less gold than in a bulk metal catalyst," Sun said. "That lowers the cost for making such a catalyst and gives the potential to scale up."



INFORMATION:

The work was funded by a National Science Foundation grant to the Brown-Yale Center for Chemical Innovation (CCI), which looks for ways to use CO2 as a sustainable feedstock for large-scale commodity chemicals. Other authors on the paper were Önder Metin, Haifeng Lv, Shaojun Guo, Christopher Wright, and Xiaolian Sun.

Editors: Brown University has a fiber link television studio available for domestic and international live and taped interviews, and maintains an ISDN line for radio interviews. For more information, call (401) 863-2476.



ELSE PRESS RELEASES FROM THIS DATE:

Aboriginal hunting practice increases animal populations

2013-10-25
Aboriginal hunting practice increases animal populations Burning approach mixing practical philosophy and knowledge leads to near doubling of lizards and improves habitat

Children with brain injuries nearly twice as likely to suffer from depression

2013-10-25
Children with brain injuries nearly twice as likely to suffer from depression Findings may help to identify, treat children at risk of depression ORLANDO, Fla. —Adults with head injuries are known to be at high risk for depression, and yet little research ...

Portable vision screening devices accurately identify vision problems in young children

2013-10-25
Portable vision screening devices accurately identify vision problems in young children New guidelines and technical advances likely to increase amblyopia screening in pediatric practice ORLANDO, Fla. —Portable screening devices allow pediatricians to successfully ...

Sleep apnea is associated with subclinical myocardial injury

2013-10-25
Sleep apnea is associated with subclinical myocardial injury Obstructive sleep apnea is known to be associated with an increased incidence of cardiovascular disease. Now a new study indicates that OSA is associated with subclinical myocardial injury, as indicated by ...

USC researcher reveals how to better master stem cells' fate

2013-10-24
USC researcher reveals how to better master stem cells' fate USC scientist Qi-Long Ying and a team of researchers have long been searching for biotech's version of the fountain of youth — ways to encourage embryonic stem cells (ESCs) and epiblast stem ...

Using sound waves for remote bomb detection

2013-10-24
Using sound waves for remote bomb detection A remote acoustic detection system designed to identify homemade bombs can determine the difference between those that contain low-yield and high-yield explosives. That capability – never before reported ...

Study: Metformin for breast cancer less effective at higher glucose concentrations

2013-10-24
Study: Metformin for breast cancer less effective at higher glucose concentrations A University of Colorado Cancer Center study published online this month in the journal Cell Cycle shows that breast cancer cell growth, motility and aggression is promoted by excess ...

NEJM study exposes overuse of radiation therapy when urologists profit from self-referral

2013-10-24
NEJM study exposes overuse of radiation therapy when urologists profit from self-referral IMRT use is 2 1/2 times greater when self-referral's financial incentives are involved Fairfax, Va., October 23, 2013—A comprehensive review of Medicare ...

UCLA sleep apnea study uncovers more hidden dangers for women

2013-10-24
UCLA sleep apnea study uncovers more hidden dangers for women There's more bad news for women with sleep apnea. A new study from the UCLA School of Nursing shows that the body's autonomic responses — the controls that impact such functions as blood ...

USC study: Google search serves users from 600 percent more locations than a year ago

2013-10-24
USC study: Google search serves users from 600 percent more locations than a year ago In a shift in strategy, Google reuses existing content delivery infrastructure to speed up searches Over the past 10 months, Google search has dramatically increased the ...

LAST 30 PRESS RELEASES:

A graphene sandwich — deposited or transferred?

New light-powered motor fits inside a strand of hair

Oil rig study reveals vital role of tiny hoverflies

Children’s Hospital of Philadelphia researchers boost widespread use of dental varnish across pediatric network

iRECODE: A new computational method that brings clarity to single-cell analysis

New NUS-MOH study: Singapore’s healthcare sector carbon emissions 18% lower than expected, a milestone in the city-state’s net zero journey

QUT scientists create material to turn waste heat into clean power

Major new report sets out how to tackle the ‘profound and lasting impact’ of COVID-19 on cardiovascular health

Cosmic crime scene: White dwarf found devouring Pluto-like icy world

Major report tackles Covid’s cardiovascular crisis head-on

A third of licensed GPs in England not working in NHS general practice

ChatGPT “thought on the fly” when put through Ancient Greek maths puzzle

Engineers uncover why tiny particles form clusters in turbulent air

GLP-1RA drugs dramatically reduce death and cardiovascular risk in psoriasis patients

Psoriasis linked to increased risk of vision-threatening eye disease, study finds

Reprogramming obesity: New drug from Italian biotech aims to treat the underlying causes of obesity

Type 2 diabetes may accelerate development of multiple chronic diseases, particularly in the early stages, UK Biobank study suggests

Resistance training may improve nerve health, slow aging process, study shows

Common and inexpensive medicine halves the risk of recurrence in patients with colorectal cancer

SwRI-built instruments to monitor, provide advanced warning of space weather events

Breakthrough advances sodium-based battery design

New targeted radiation therapy shows near-complete response in rare sarcoma patients

Does physical frailty contribute to dementia?

Soccer headers and brain health: Study finds changes within folds of the brain

Decoding plants’ language of light

UNC Greensboro study finds ticks carrying Lyme disease moving into western NC

New implant restores blood pressure balance after spinal cord injury

New York City's medical specialist advantage may be an illusion, new NYU Tandon research shows

Could a local anesthetic that doesn’t impair motor function be within reach?

1 in 8 Italian cetacean strandings show evidence of fishery interactions, with bottlenose and striped dolphins most commonly affected, according to analysis across four decades of data and more than 5

[Press-News.org] Gold nanoparticles give an edge in recycling CO2